1. Field of the Invention
The present invention relates to optically active quinolonecarboxylic acid derivatives which exhibit high antibacterial activity and safety and have remarkable stability, and to an antibacterial composition containing such a derivative.
2. Related Art
Quinolonecarboxylic acid derivatives are a class known as synthetic antibacterial agents. Particularly, compounds of the following formula (I) having a 1,2-cis-2-halogenocyclopropyl group on the nitrogen atom at the 1-position of the quinolone skeletone exhibit strong antibacterial activity and safety, and thus are known to be useful as pharmaceutical agents (Japanese patent No. 2714597 and 2917010); wherein R1 is an amino group, a methylamino group, a hydroxyl group, a thiol group, or a hydrogen atom; and R2 is a substituent selected from the group consisting of the following groups: (wherein R3, R4, R5, and R6 each independently represents a hydrogen atom or a C1-C6 alkyl group, R10 and R11 each independently represents a hydrogen atom or a C1-C6 alkyl group, R12 and R13 each independently represents a hydrogen atom or a C1-C6 alkyl group or R12 and R13 may form a polymethylene chain of from 2 to 5 carbon atoms), or a 3-hydroxypyrrolidinyl group which may have a C1-C6 alkyl group; A represents C-X3 or a nitrogen atom; X1 and X2 each independently represents a halogen atom; X3 represents a halogen atom, a C1-C6 alkyl group, a C1-C6 alkoxy group, trifluoromethyl group, or a hydrogen atom; and Z represents a hydrogen atom, a C1-C6 alkyl group, a C1-C6 alkoxyalkyl group, a phenylalkyl group of C1-C6 alkyl, a phenyl group, an acetoxymethyl group, a pivaloyloxymethyl group, an ethoxycarbonyloxy group, a chorine group, a dimethylaminoethyl group, a 5-indanyl group, a phthalidinyl group, a 5-substituted-2-oxo-1,3-dioxol-4-ylmethyl group, or a 3-acetoxy-2-oxobutyl group; with the case in which R2 is a 3-aminopyrrolidinyl group and R1 and X3 are hydrogen atoms being excluded.
A variety of fluoroquinolone synthetic antibacterial agents have been developed to provide clinical drugs for chemotherapy which are effective in the treatment of a broad range of systemic infectious diseases. Nevertheless, demands still exist for compounds which exhibit higher antibacterial activity, which are safer than the previous compounds, and in addition, which are endowed with excellent stability against light and humidity.